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If I was to build an artificial backstop at 100 Mtrs for siting in and use say six strainers posts then all walled in with 6 x 2 timber so a box then filled with sand anyone know how wide the box should be to prevent any shots exiting the rear wall.
I was thinking 1.8 high by 2.0 long and unsure of required width .I d just fill the sand part with tractor bucket
Up to 300 win mag calibre ??
Cheers
Doesn't take much sand to stop a bullet. half a meter.
Chopped up rubber tyres work better than sand and is water resistant and won't pack down, it's used on military and police ranges here and abroad
the 100 metre range at Ardmore was done with it worked great, it would pay to check with your local council and arms office in case the
neighbours start complaining.
Chopped up tyre does work but make sure you allow for fire. Especially if some dolt uses tracer etc. For testing set up a board wtith packed sand behind it and shoot it up close and dig out the bullet to find out how far it travelled. Then add an extra buffer in case you get a bigger calibre later and go from there.Quote:
Originally Posted by shooternz
Finally, make sure that whatever is behind the backstop is a clear firing zone (IE nothing there that could be damaged by a stray etc. ) Better to be paranoid and not need it than wrong.....
The chopped up rubber is impressive. We use it in drums at our fullbore range and nothing gets through it unless the bullet slips down the outside edges. That's why you need the drums in staggered rows
Where do you get the rubber?
Pacific rubber.co.nz is one option.
Quite amazing the number of uses for old tyres.
At a place I lived I had a pile of dirt 5metres deep that I used as a back stop for load testing. Over a period of 12 months the projectiles created a 100mm channel right through the dirt pile.
The Royal Canadian Mounted Police Range Design Manual has some good design info on safety templates ,cones of fire, backstop design requirements etc. This is the manual that most other design manuals have been based on over the years.
Most of their backstop designs are the traditional earth butts whereas for the new NZDA BOP Branch range we built in Tauranga we used vertical backstops with two rows of 200l plastic drums filled with shredded rubber as bullet catchers in front of this.
I see your in the Waikato. We sourced the shredded rubber from Carbon Recover in Waharoa.
PM me if you want a copy of the Canadian manual
Cheers
Grant
Suggestion, go simple. Tires, imported sand, etc all create end of use issues.
Softwood facing ( like you suggest) back end softwood, gap filled with native/local soil. If possible, you only really need the front to be faced with wood and the back can taper down , think triangle of local soil. Sort of like a truck loading ramp.
End of use, you can 'mine' any lead and then just flatten the remaining soil.
The candain manual is really good for depth of cover etc... And in fact alot of nz cert standards for ranges are based off them.
Gimp is on it though .5m and your about right, and if triangle based, by the time you get above the target area(top) at .5m, the target has way more than that beind it.
So, 2-3 posts, a few retaining boards and pile up the local dirt. One thing that can help with erosion of the back wall is facing the wood with conveyor belt, sort of self seals. Oh and of course the over shot area etc......